--- /usr/local/src/asterisk/asterisk-18.1.0/contrib/systemd/asterisk.service	2020-11-19 13:39:40.000000000 +0100
+++ /usr/lib/systemd/system/asterisk.service	2020-12-17 15:30:19.341284656 +0100
@@ -1,15 +1,22 @@
 [Unit]
 Description=Asterisk PBX and telephony daemon.
 After=network.target
+#include these if asterisk need to bind to a spicifik IP (other than 0.0.0.0
+#Wants=network-online.target
+#After=network-online.target network.target
 
 [Service]
 Type=notify
 Environment=HOME=/var/lib/asterisk
+#if systemd do not provide hostname and you need to use ${ENV(HOSTNAME)}
+#Environment=HOSTNAME=%H
 WorkingDirectory=/var/lib/asterisk
 User=asterisk
 Group=asterisk
 ExecStart=/usr/sbin/asterisk -mqf -C /etc/asterisk/asterisk.conf
 ExecReload=/usr/sbin/asterisk -rx 'core reload'
+#if linux rebuild /var/run on restart, this will crerate it on start
+#RuntimeDirectory=asterisk
 
 #Nice=0
 #UMask=0002